pdf_type='xxx'; OR: pdf_type='xxx_yyy';but the function pdf_xxx.m must exist (use software/pdf_gauss.m or software/pdf_gmm.m as templates). If the suffix _yyy or _yyy_zzz, etc, is added to the pdf_type variable, the character string , 'yyy' or yyy_zzz will be passed to the function pdf_xxx.m as input variable pstr. To see how this works, look at software/pdf_gmm.m. The parameter 'yyy' defines the number of mixture components, for example
pdf_type='gmm_2';specifies a Gaussian mixture with two mixture components.